KR20080056293A - Polishing solution for cmp and method of polishing - Google Patents

Abstract

A polishing solution for CMP that inhibits any electron transfer in the vicinity of boundary region between a barrier conductor and a conductive substance, such as copper, to thereby inhibit any conductive substance wiring corrosion, namely, bimetallic corrosion between the barrier conductor and the conductive substance. There is provided a polishing solution for CMP used to polish at least a conductor layer and a conductive substance layer in contact with the conductor layer wherein when an electrometer at its positive electrode side is connected to the conductive substance and at its negative electrode side connected to the conductor, the absolute value of potential difference exhibited at 50±5°C between the conductive substance and the conductor is 0.25 V or less. Preferably, at least one member selected from among heterocyclic compounds having any of hydroxyl, carbonyl, carboxyl, amino, amido and sulfinyl and containing at least either a nitrogen or a sulfur atom is contained in the polishing solution.

Description

Polishing solution and polishing method for CPM {POLISHING SOLUTION FOR CMP AND METHOD OF POLISHING}

The present invention relates to a polishing liquid for CMP and a polishing method used for polishing in a wiring forming step of a semiconductor device.

In recent years, new fine processing techniques have been developed in accordance with high integration and high performance of semiconductor integrated circuits (hereinafter referred to as LSI). The chemical mechanical polishing (hereinafter, referred to as CMP) method is one of them, and is a technique frequently used in the planarization of the interlayer insulating film, the metal plug formation, and the buried wiring formation in the LSI manufacturing process, especially in the multilayer wiring formation process. This technique is disclosed, for example, in US Pat. No. 4,944,836.

In recent years, in order to improve the performance of LSI, use of copper and copper alloys has been attempted as a conductive material serving as a wiring material. However, in the formation of conventional aluminum alloy wirings, although fine processing by the dry etching method is frequently used, it is difficult to use in copper or a copper alloy. Therefore, a so-called damascene process in which a thin film of copper or a copper alloy is deposited and buried on an insulating film in which grooves are formed in advance, and then the thin film other than the groove portion is removed by CMP to form a buried wiring. Mainly adopted. This technique is disclosed, for example, in Japanese Patent No. 1969537.

The general method of metal CMP for polishing metal for wiring parts, such as copper or a copper alloy, is to adhere a polishing cloth (pad, pad) on a circular polishing plate (platen), the surface of the polishing cloth for the metal polishing liquid While wetting with, the surface on which the metal film of the substrate was formed is pressed on the surface of the polishing cloth, and the polishing platen is rotated while applying a predetermined pressure (hereinafter referred to as polishing pressure) to the metal film from the back surface of the polishing cloth. As a result, the metal film of the convex portion is removed by the relative mechanical friction between the polishing liquid and the convex portion of the metal film.

The slurry polishing liquid for metals used for CMP generally contains an oxidizing agent and an abrasive grain, and a metal oxide dissolving agent and a protective film forming agent are further added as needed. First, the basic mechanism is considered to oxidize the surface of a metal film with an oxidizing agent and to cut the oxide layer by abrasive grains. Since the oxide layer of the metal surface of the concave portion hardly touches the polishing pad, and there is no cutting effect due to the abrasive grains, the metal layer of the convex portion is removed with the progress of the CMP, and the substrate surface is flattened. Details are disclosed in the Journal of Electrochemical Society, Vol. 138, No. 11 (published in 1991), pages 3460-3464.

It is effective to mix | blend a metal oxide solubilizer as a method of improving the polishing rate by CMP. It is interpreted that dissolving the kernels of metal oxides cut by the abrasive grains in the polishing liquid (hereinafter referred to as etching) increases the cutting effect by the abrasive grains. Although the polishing rate by CMP improves by mix | blending a metal oxide dissolving agent, when the oxide layer of the metal film surface of a recessed part is also etched and the metal film surface is exposed, the metal film surface will be oxidized again by an oxidant. If this is repeated, etching of the metal film of the recess proceeds. For this reason, the phenomenon that the center part of the surface of the metal wiring embedded after grinding is recessed like a dish (hereinafter referred to as dishing) occurs, and the planarization effect is impaired.

In order to prevent this, a protective film forming agent is further mix | blended. A protective film forming agent forms a protective film on the oxide layer on the surface of a metal film, and prevents melt | dissolution of an oxide layer into the polishing liquid. It is preferable that this protective film can be easily cut by an abrasive grain, and does not reduce the polishing rate by CMP.

In order to suppress corrosion during dishing and polishing of copper or copper alloys and to form highly reliable LSI wirings, metal oxide solubilizers containing aminoacetic acid or amic sulfuric acid such as glycine, and CMP containing BTA as a protective film forming agent. A method of using a polishing liquid is known. This technique is described, for example, in Japanese Patent No. 3397501.

On the other hand, in the lower layer of the metal for wiring parts, such as copper or a copper alloy, as a barrier conductor layer (henceforth a barrier layer) for preventing copper diffusion into an interlayer insulation film, or improving adhesiveness, it is a tantalum, tantalum alloy, tantalum nitride, for example. Layers, such as a tantalum compound, are formed. Therefore, it is necessary to remove the exposed barrier layer by CMP except the wiring portion which embeds copper or copper alloy. However, since the conductors of these barrier layers have higher hardness than copper or copper alloys, even when a polishing material for copper or a copper alloy is combined, a sufficient polishing rate is not obtained and the flatness is often worsened. Accordingly, a two-stage polishing method including a first step of polishing the wiring portion metal and a second step of polishing the barrier layer has been studied.

In the second polishing step of polishing the barrier layer, the interlayer insulating film must also be polished to improve flatness. Although silicon oxide films are mainly used as interlayer insulating films, recently, in order to improve LSI performance, use of silicon-based materials or organic polymers having a lower dielectric constant than silicon oxide films has been attempted.

<Start of invention>

In the so-called isolated copper fine wiring on the substrate, in which the wiring width is 0.5 탆 or less and the wiring distance is about 5.0 탆 or more after the second polishing process of polishing the barrier layer, the corrosion of the tip end and the barrier conductor and Corrosion of the boundary of copper or a step (recess) of hardness tends to occur. For this reason, in manufacturing a high performance semiconductor device which requires high reliability in which fine wirings are indispensable, defects such as disconnection, yield and reliability can be caused. As a cause of this corrosion, the dissimilar metal contact corrosion of a barrier conductor and copper can be considered. When the potential difference between the barrier conductor and the copper is somewhat increased, electrons and copper ions are eluted from the surface of copper near the boundary between the barrier conductor and the copper in the polishing liquid, and corrosion may occur.

In view of the above problems, the present invention suppresses dissimilar metal contact corrosion between the barrier conductor and the conductive material, that is, suppresses the corrosion of the conductive material wiring by suppressing the movement of electrons near the boundary between the conductive material such as the barrier conductor and copper. It is to provide a polishing liquid for CMP.

As a confirmation method of the CMP polishing liquid which can suppress the wiring corrosion of a conductive material, it is preferable to measure the potential difference of a barrier conductor and a conductive material via a polishing liquid, and to confirm that the absolute value of the potential difference is small.

The polishing liquid of the present invention is characterized in that the absolute value of the potential difference between the conductor for the barrier layer and the conductive substance in the polishing liquid is small. Here, at least one selected from a heterocyclic compound containing any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group and a sulfinyl group and further containing at least one of a nitrogen and a sulfur atom, or an amine compound, By containing at least 1 type selected from an amide compound and a sulfoxide compound in a polishing liquid, a protective film is formed on the surface of an electroconductive substance. As a result, it is thought that electrons and conductive material ions are prevented from eluting from the surface of the conductive material near the boundary between the barrier conductor and the conductive material in the polishing liquid, and the dissimilar metal contact corrosion between the barrier conductor and the conductive material can be suppressed. .

That is, this invention relates to the CMP polishing liquid of the following (1)-(21).

(1) The absolute value of the potential difference between the conductive material and the conductor at 50 ± 5 ° C. in the polishing liquid when the positive electrode side of the electrometer is connected to the conductive material and the conductor is 0.25 V or less, at least the conductor layer and A CMP polishing liquid for polishing a conductive material layer in contact with the conductor layer.

(2) The polishing liquid for CMP according to (1), which contains an additive for lowering the absolute value of the potential difference between the conductor and the conductive material.

(3) The additive according to (2), wherein the additive contains a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group, and at least one of nitrogen and sulfur atoms. Polishing liquid for CMP containing 1 or more types chosen from heterocyclic compounds to be mentioned.

(4) The CMP polishing liquid according to (3), wherein the heterocyclic compound has a solubility of the copper complex formed when copper (II) is added to the polishing liquid to the polishing liquid at a liquid temperature of 25 ° C.

(5) The polishing liquid for CMP according to (2), which contains at least one selected from an amine compound, an amide compound, and a sulfoxide compound as an additive for lowering the absolute value of the potential difference.

(6) The compound according to any one of (3) to (5), which contains any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group, and further contains at least one of a nitrogen and a sulfur atom. Polishing liquid for CMP containing 1 or more types chosen from a summoning compound, and 1 or more types chosen from an amine compound, an amide compound, and a sulfoxide compound.

(7) The conductor according to any one of (1) to (6), wherein the conductor is tantalum, tantalum nitride, tantalum alloy, other tantalum compound, titanium, titanium nitride, titanium alloy, other titanium compound, tungsten, tungsten nitride, Tungsten alloy, other tungsten compounds, ruthenium, and at least one selected from other ruthenium compounds, the conductive material is copper, copper alloys, oxides of copper, oxides of copper alloys, tungsten, tungsten alloys, silver, silver Polishing liquid for CMP which is alloy or gold.

(8) The polishing liquid for CMP according to any one of (1) to (7), wherein the conductive material is copper.

(9) a conductive material (a) containing copper as a main component, and

Selected from tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys, other tungsten compounds, ruthenium, and other ruthenium compounds At least one conductor (b)

Is a polishing liquid for polishing a to-be-polished surface having a surface thereof, and a conductive material at 50 ± 5 ° C. in a polishing liquid when the positive electrode side of the electrometer is connected to the conductive material (a) and the negative electrode side is connected to the conductive material (b) ( The polishing liquid for CMP, characterized in that the absolute value of the potential difference between a) and the conductor (b) is 0.25 V or less.

(10) an interlayer insulating film having a concave portion and a convex surface, a barrier conductor layer covering the interlayer insulating film along the surface, and a conductive material layer mainly composed of copper filling the concave portion to cover the barrier conductor layer; At least one heterocyclic compound containing a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group, and at least one of nitrogen and sulfur atoms; A polishing liquid for CMP comprising a.

(11) a conductive material (a) containing copper as a main component, and

Selected from tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys, other tungsten compounds, ruthenium, and other ruthenium compounds At least one conductor (b)

Is a polishing liquid for polishing a surface to be polished having a surface thereof, a heterocyclic compound containing any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group and a sulfinyl group, and containing at least one of nitrogen and sulfur atoms Polishing liquid for CMP containing 1 or more types chosen from.

(12) an interlayer insulating film having a concave portion and a convex portion having a surface, a barrier conductor layer covering the interlayer insulating film along the surface, and a conductive material layer mainly composed of copper filling the concave portion to coat the barrier conductor layer; A polishing liquid for polishing a substrate, wherein the polishing liquid for CMP contains at least one selected from an amine compound, an amide compound, and a sulfoxide compound.

(13) a conductive material (a) containing copper as a main component, and

Selected from tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys, other tungsten compounds, ruthenium, and other ruthenium compounds At least one conductor (b)

A polishing liquid for polishing a surface to be polished having a surface thereof, wherein the polishing liquid for CMP contains at least one selected from an amine compound, an amide compound, and a sulfoxide compound.

(14) The CMP polishing liquid according to any one of (1) to (13), which contains abrasive particles.

(15) The CMP polishing liquid according to (14), wherein the abrasive particles are at least one selected from silica, alumina, ceria, titania, zirconia, and germania.

(16) The polishing liquid for CMP according to any one of (1) to (15), which contains a metal oxide solubilizer and water.

(17) The polishing liquid for CMP according to (16), wherein the metal oxide solubilizer is at least one selected from an organic acid, an organic acid ester, an ammonium salt of an organic acid, and an inorganic acid.

(18) The CMP polishing liquid according to any one of (1) to (17), which contains a metal corrosion inhibitor.

(19) The method of (18), wherein the metal corrosion inhibitor has a triazole skeleton, a benzotriazole skeleton, a pyrazole skeleton, a pyramidine skeleton, an imidazole skeleton, guanidine Polishing liquid for CMP which is 1 or more types chosen from having a skeleton and having a thiazole skeleton.

(20) The CMP polishing liquid according to any one of (1) to (19), which contains an oxidizing agent of a metal.

(21) The polishing liquid for CMP according to (20), wherein the metal oxidant is at least one selected from hydrogen peroxide, nitric acid, potassium periodate, hypochlorous acid, and ozone water.

Moreover, this invention relates to the grinding | polishing method of the following (22)-(25).

(22) In a substrate having an interlayer insulating film having a concave portion and a convex surface, a barrier layer covering the interlayer insulating film along the surface, and a conductive material layer filling the concave portion to cover the barrier layer, The first polishing step of polishing to expose the barrier layer of the convex portion, and the chemical mechanical polishing of at least the barrier layer and the conductive material layer of the concave portion while supplying the polishing liquid for CMP according to any one of the above (1) to (21). And a second polishing step of exposing the interlayer insulating film of the convex portion.

(23) The polishing method according to (22), wherein the interlayer insulating film is a silicon film or an organic polymer film.

(24) The polishing method according to (22) or (23), wherein the conductive material contains copper as a main component.

(25) The method of any one of (22) to (24), wherein the barrier conductor layer prevents the conductive material from diffusing into the interlayer insulating film, and includes tantalum, tantalum nitride, tantalum alloy, other tantalum compounds, titanium, A polishing method comprising one or more selected from titanium nitride, titanium alloy, other titanium compounds, tungsten, tungsten nitride, tungsten alloy, other tungsten compounds, ruthenium, and other ruthenium compounds.

The disclosure of this application is related to the subject matter of Japanese patent application 2005-298031 for which it applied on October 12, 2005, The content of these is integrated in this application as a reference.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of an example of the measuring method of the potential difference in this invention.

(Explanation of the sign)

1: glass beaker

2: polishing liquid for CMP

3: barrier conductor substrate

4: copper substrate

5: electrometer

Best Mode for Carrying Out the Invention

The polishing liquid for CMP of the present invention is a polishing liquid for polishing at least the conductor layer and the conductive material layer in contact with the conductor layer, wherein the absolute value of the potential difference between the conductor and the conductive material measured in the polishing liquid is small. . As a result, corrosion of the conductive material fine wiring can be suppressed. At this time, it is preferable to suppress the absolute value of the potential difference between the conductor and the conductive material in the polishing liquid to 0.25 V or less.

The polishing liquid of the present invention is a polishing liquid that can be used for polishing a to-be-polished surface having a conductive material shown below and a conductor shown below. Specifically, the to-be-polished surface is filled with the interlayer insulation film whose surface consists of a recessed part and convex part in the wiring part formation process of a semiconductor device, the barrier conductor layer which coats the said interlayer insulation film along the surface, and the said recessed part. The board | substrate which has an electroconductive material layer whose main component is copper which coat | covers a barrier conductor layer is mentioned.

Examples of the conductive material include metals such as copper, copper alloys, copper oxides, copper alloy oxides, tungsten, tungsten alloys, silver, silver alloys, and gold. Conductive materials in which copper is a main component (hereinafter also referred to as conductive material (a)) are preferable, and examples thereof include copper, copper alloys, oxides of copper, and oxides of copper alloys. More preferably, it is copper. As a conductive material layer containing such a conductive material, the metal layer for wiring parts in a semiconductor device is mentioned, for example.

1 selected from tungsten, tungsten nitride, tungsten alloy, other tungsten compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, ruthenium and other ruthenium compounds as conductors Species or more (hereinafter also referred to as conductor (b)) are illustrated. The conductor layer may be a layer containing the conductor (b) or a laminated film including the layer. Examples of the conductor layer include a barrier conductor layer formed in the semiconductor device for preventing diffusion of the conductive material into the interlayer insulating film and improving adhesion between the interlayer insulating film and the conductive material.

Moreover, it is preferable that the CMP polishing liquid of this invention contains the additive which lowers the absolute value of the potential difference of a conductor and a conductive substance. It is also preferable to contain abrasive particles, metal oxide solubilizers, metal corrosion inhibitors and water. More preferably, the metal contains an oxidizing agent. Moreover, the solvent which can be mixed with water, such as an organic solvent, a water-soluble polymer, a coloring agent, etc. can also be mix | blended as needed.

In the polishing liquid of the present invention, the absolute value of the potential difference between the conductive material and the conductor in the liquid is preferably 0.25 V or less. When the absolute value of the potential difference is 0.25 V or less, dissimilar metal contact corrosion between the conductive material and the conductor, that is, corrosion of the conductive material wiring is unlikely to occur. If the value exceeds 0.25 V, the absolute value of the potential difference between the conductor and the conductive material is somewhat increased, so that ions of the electron and the conductive material are eluted from the surface of the conductive material near the boundary between the conductor and the conductive material in the polishing liquid, and the conductive material wiring Corrosion is likely to occur. In addition, when the absolute value of the potential difference is 0.20 V or less, corrosion of the conductive material wiring is less likely to occur.

In the present invention, the absolute value of the potential difference between the conductive material and the conductor is measured by the following procedure. That is, about 50 ml of polishing liquid is put into a beaker with a capacity of about 100 ml, and it is set to 50 +/- 5 degreeC in a thermostat. The polishing liquid is a polishing liquid at the time of CMP polishing, and is a polishing liquid after actually adding an additive such as an oxidizing agent of metal which may be added immediately before chemical mechanical polishing. A silicon substrate (hereinafter referred to as a conductive material substrate) on which a conductive material film is formed by sputtering method and a silicon substrate (hereinafter referred to as a conductor substrate) on which a conductor film such as tantalum is formed by sputtering method are set to an appropriate size, and the positive electrode of the electrometer The side is connected to the conductive material substrate and the negative electrode side is connected to the conductor substrate. Then, the minimum value of the absolute value of the potential difference measurement value 30 minutes after immersion in the polishing liquid with the conductive material substrate and the conductor substrate spaced apart from each other is adopted as the potential difference absolute value. The material of the beaker is not particularly limited as long as it does not react with the polishing liquid, but glass or plastic is preferable.

As a method of reducing the absolute value of the potential difference between a conductor and a conductive material, the polishing liquid contains an additive which has an effect of suppressing the movement of electrons near the boundary between the conductor and the conductive material. The additive which lowers the absolute value of the potential difference between the conductor and the conductive material (hereinafter referred to as an additive that lowers the potential difference), which has the effect of suppressing the movement of electrons near the boundary between the conductor and the conductive material, is not particularly limited. And one or more (A) selected from sulfoxide compounds. Moreover, it contains any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group, and also contains 1 or more types (B) chosen from the heterocyclic compound containing at least one of a nitrogen and a sulfur atom. It is preferable. Moreover, you may use together and use said (A) and (B).

The following are illustrated as an amine compound among the compounds contained in said (A). Alkanolamines such as monoethanolamine, N, N-dimethylethanolamine, N-methyl diethanolamine, and triethanolamine; aliphatic amines such as n-propylamine, butylamine, dibutylamine, tributylamine, 1,4-butanediamine, triethylenetetramine and cyclohexylamine; Aromatic amines such as aniline, N-methylaniline, N-ethylaniline, and aromatic polyamines.

Examples of the amide compound include dimethylformamide, dimethylacetamide, and hexamethylphosphoric triamide. Examples of the sulfoxide compound include dimethyl sulfoxide and the like.

As a heterocyclic compound contained in the said (B), pyrazine amide, pyrazine-2, 3- dicarboxylic acid monoamide, pyrazine carboxylic acid, 2, 3- pyrazine dicarboxylic acid, 1-hydroxy benzotriazole , 2-amino-2-thiazoline acetic acid, 3,5-dimethylpyrazole, pyrazinecarboxamide, 4-amino-1,2,4-triazole, 1,2,4-triazol-3-one, etc. This is illustrated.

Among the additives for lowering the potential difference, monoethanolamine, ethylamine, n-propylamine, n-butylamine, dibutylamine, tributylamine, 1,4-butanediamine, cyclohexylamine, triethylenetetramine, N, N-dimethylethanolamine, N-methyldiethanolamine, triethanolamine, hexamethylphosphoric triamide, aniline, N-methylaniline, N-ethylaniline, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, pyrazineamide, Pyrazine-2,3-dicarboxylic acid monoamide, pyrazinecarboxylic acid, 2,3-pyrazinedicarboxylic acid, 1-hydroxybenzotriazole, 2-amino-2-thiazoline acetic acid, 3,5- Dimethylpyrazole, pyrazinecarboxamide, 4-amino-1,2,4-triazole, 1,2,4-triazol-3-one are preferred, monoethanolamine, N, N-dimethylethanolamine, N-methyldiethanolamine, triethanolamine, n-butylamine, hexamethylphosphoric triamide, aniline, cyclohexyl a , Dimethyl sulfoxide, dimethylacetamide, pyrazinecarboxylic acid, 2,3-pyrazinedicarboxylic acid, 1-hydroxybenzotriazole, 2-amino-2-thiazoline acetic acid, 3,5-dimethylpyrazole, More preferred are pyrazinecarboxamide, 4-amino-1,2,4-triazole, 1,2,4-triazol-3-one, and N-dimethylethanolamine, triethanolamine, aniline, 4-amino- More preferred are 1,2,4-triazole, 1-hydroxybenzotriazole, pyrazinecarboxylic acid, and 2,3-pyrazinedicarboxylic acid.

These can be used individually by 1 type or in mixture of 2 or more types.

As an additive which lowers the potential difference in the polishing liquid of the present invention, (B) contains any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group and a sulfinyl group, and further contains at least one of nitrogen and sulfur atoms. When using a heterocyclic compound, it is preferable that the solubility of the copper complex produced | generated when copper sulfate (II) is added to polishing liquid to 1 weight% or more at 25 degreeC of liquid temperature is preferable. When the said heterocyclic compound which is the said solubility of 1 weight% or more is mix | blended, absolute potential difference value will become small, On the contrary, when the said solubility contains the heterocyclic compound which is less than 1 weight%, there exists a tendency for absolute potential difference value to become large.

In addition, in this invention, the said solubility is measured as follows. Copper (II) sulfate is appropriately added to the CMP polishing liquid and stirred well, then the liquid temperature is maintained at 25 ° C. and left for 60 minutes to confirm the presence or absence of deposits in the vessel. The addition amount of copper (II) sulfate is preferably 0 to 10 g (except 0) with respect to 100 g of the polishing liquid, and the (B) heterocyclic compound and copper (II) ions have two molar concentrations. It is particularly preferable to form a complex with 1 and add half of the molar concentration of the (B) heterocyclic compound in the polishing liquid.

Examples of the abrasive particles in the present invention include inorganic abrasive particles such as silica, alumina, zirconia, ceria, titania, germania, and silicon carbide, and organic abrasive particles such as polystyrene, polyacryl, and polyvinyl chloride. Silica, alumina, zirconia, ceria, titania, and germania are preferred, and particularly, the dispersion stability in the polishing liquid is good, the number of occurrence of polishing scratches (scratches) caused by CMP is small, and the colloidal property with an average particle diameter of 70 nm or less. Silica and colloidal alumina are preferable, and colloidal silica and colloidal alumina whose average particle diameter is 40 nm or less are more preferable. Moreover, the particle | grains which the primary particle aggregated less than an average of 2 particle | grains are preferable, and the particle | grains which primary particle aggregated less than 1.2 particle | grains are more preferable. Moreover, it is preferable that the standard deviation of average particle size distribution is 10 nm or less, and it is more preferable that the standard deviation of average particle size distribution is 5 nm or less. These can be used individually by 1 type or in mixture of 2 or more types.

Colloidal silica is known to be produced by hydrolysis of silicon alkoxide or ion exchange of sodium silicate, and colloidal alumina is known to be produced by hydrolysis of aluminum nitrate. Colloidal silica is most commonly used by the production method by hydrolysis of silicon alkoxide from the viewpoint of particle size controllability and alkali metal impurities. As the silicon alkoxide, TEMS (tetramethoxysilane) or TEOS (tetraethoxysilane) is generally used. In the method of hydrolyzing in an alcohol solvent, the parameters affecting the particle size include the concentration of silicon alkoxide, the ammonia concentration and pH used as a catalyst, the reaction temperature, the type of alcohol solvent (molecular weight), the reaction time, and the like. have. By adjusting these parameters, a colloidal silica dispersion liquid having a desired particle size and agglomeration degree can be obtained.

The metal oxide solubilizer in the present invention is not particularly limited, and examples thereof include organic acids, organic acid esters, ammonium salts of organic acids, inorganic acids, and ammonium salts of inorganic acids. Among them, formic acid, malonic acid, malic acid, tartaric acid, citric acid, salicylic acid, adipic acid, phthalic acid, and polyacrylic acid are mainly conductive metals in that the etching rate can be effectively suppressed while maintaining a practical CMP rate. It is preferable for the conductive material whose sulfuric acid is mainly composed of metal in terms of high CMP rate. These can be used individually by 1 type or in mixture of 2 or more types.

Although the metal corrosion inhibitor in this invention does not have a restriction | limiting in particular, It has a triazole skeleton, a pyrazole skeleton, a pyramidine skeleton, an imidazole skeleton, a guanidine skeleton, a thiazole And having a skeleton. These can be used individually by 1 type or in mixture of 2 or more types. In addition, the heterocyclic compound contained in (B) among the additives which lowers the above-described potential difference may be used as the metal corrosion inhibitor.

You may mix | blend a metal oxidizing agent with the CMP polishing liquid of this invention. Examples of the metal oxidizing agent include hydrogen peroxide, nitric acid, potassium periodate, hypochlorous acid, ozone water, and the like, and hydrogen peroxide is particularly preferable. These can be used individually by 1 type or in mixture of 2 or more types. When the substrate is a silicon substrate including an integrated circuit element, contamination by alkali metal, alkaline earth metal, halide or the like is not preferable, and therefore, an oxidant containing no nonvolatile component is preferable. Hydrogen peroxide is most suitable for ozone water because of its time-varying composition. However, in the case where the substrate to be applied is a glass substrate or the like which does not contain a semiconductor element, it may be an oxidizing agent containing a nonvolatile component.

Moreover, a solvent can also be mix | blended with the CMP polishing liquid of this invention. Although there is no restriction | limiting in particular as a solvent in the CMP polishing liquid of this invention, The organic solvent which can be mixed arbitrarily with water is preferable. For example, glycols, glycol monoethers, glycol diethers, alcohols, carbonate esters, lactones, ethers, ketones, other phenols, dimethylformamide, n-methylpyrrolidone, ethyl acetate, lactic acid Ethyl, sulfolane and the like. Preferably, it is 1 or more types chosen from glycol monoethers, alcohols, and carbonate esters.

When mix | blending the additive which lowers an electric potential difference in the grinding | polishing liquid of this invention, it is preferable to set the compounding quantity of the said additive to 0.001-10g with respect to 100g of grinding | polishing liquid, It is more preferable to set it as 0.005-5g, 0.01-1g It is especially preferable to set it as. If the blending amount is less than 0.001 g, the effect of reducing the absolute value of the potential difference tends to be low, and if it exceeds 10 g, the polishing rate is lowered, and the flatness after pattern wafer polishing tends to be deteriorated.

In the case of blending the abrasive grains, the blending amount of the abrasive grains in the present invention is preferably 0.01 to 50 g, more preferably 0.02 to 20 g, particularly preferably 0.05 to 10 g with respect to 100 g of the polishing liquid. desirable. If the compounding amount is less than 0.01 g, the polishing rate tends to be low, and if it exceeds 50 g, the polishing scratch tends to occur.

When mix | blending a metal oxide dissolving agent, the compounding quantity of the metal oxide dissolving agent in this invention is preferably 0.001-20 g with respect to 100 g of polishing liquid, It is more preferable to set it as 0.002-10 g, It is 0.005-5 g Is particularly preferred. When the compounding amount is less than 0.001 g, the polishing rate tends to be low, and when it exceeds 20 g, the etching is difficult to be suppressed, and the polishing surface tends to be rough.

When mix | blending a metal corrosion inhibitor, it is preferable to make the compounding quantity of the metal corrosion inhibitor in this invention into 0-10g (but except 0) with respect to 100g of polishing liquid, and it is more preferable to set it as 0.001-5g. It is preferable and it is especially preferable to set it as 0.002-2g. When this compounding quantity exceeds 10 g, it exists in the tendency for a grinding | polishing rate to become low.

When mix | blending the oxidizing agent of a metal, it is preferable to set the compounding quantity of the oxidizing agent of the metal in this invention to 0.01-50 g with respect to 100 g of polishing liquid, It is more preferable to set it as 0.02-20 g, It is 0.05-10 g It is particularly preferable to. If the blending amount is less than 0.01 g, the oxidation of the metal is insufficient and the CMP rate tends to be low, and if it exceeds 50 g, the polishing surface tends to be rough.

When mix | blending an organic solvent, the compounding quantity of the organic solvent in this invention has preferable 0.1-95g with respect to 100g of polishing liquid, It is more preferable to use 0.2-50g, It is especially preferable to set it as 0.5-10g desirable. If the blending amount is less than 0.1 g, the wettability of the polishing liquid to the substrate tends to be low, and if it exceeds 95 g, the risk of ignition increases, which is not preferable in the manufacturing process. In addition, the compounding quantity of water may be remainder, and there is no restriction | limiting in particular.

In addition to the various components described above, the polishing liquid of the present invention may also contain a water-soluble polymer, a colorant, or the like as necessary.

The polishing liquid of the present invention as described above can be applied to the formation of a wiring layer in a semiconductor device. For example, it can be used for chemical mechanical polishing (CMP) of a conductive material layer, a barrier layer, and an interlayer insulation film. In the polishing method of the present invention, in a substrate having an interlayer insulating film having a concave portion and a convex portion, a barrier layer covering the interlayer insulating film along the surface, and a conductive material layer filling the concave portion to cover the barrier layer, A first polishing step of polishing the conductive material layer to expose the barrier layer of the convex portion, and a second polishing of polishing at least the barrier layer and the conductive material layer of the concave portion, and optionally by further polishing the interlayer insulating film. Process. Then, in the second polishing step, chemical mechanical polishing is performed while supplying the polishing liquid of the present invention.

In the chemical mechanical polishing, the polishing surface is polished by relatively moving the polishing surface and the substrate while supplying the polishing liquid while pressing the substrate having the polishing surface onto the polishing cloth (pad) of the polishing table. A method is mentioned. In addition, in order to planarize, the method of contacting a metal or resin brush, and the method of spraying polishing liquid at predetermined pressure are mentioned.

As an electroconductive substance, the substance whose main component is a metal is mentioned as mentioned above, A electroconductive substance (a) is preferable and copper is more preferable. As the conductive material layer, a film in which the material is formed by a known sputtering method or a plating method can be used.

As mentioned above, a barrier layer containing tungsten, titanium, another conductor (b), and the laminated film containing this barrier layer are mentioned as mentioned above.

Examples of the interlayer insulating film include a silicon film and an organic polymer film. Examples of the silicone coating include silica films such as silicon dioxide, fluorosilicate glass, organosilicate glass obtained by using trimethylsilane and dimethoxydimethylsilane as starting materials, silicon oxynitride, hydrogenated silsesquioxane, silicon carbide and Silicon nitride. Moreover, as an organic polymer film, a wholly aromatic low dielectric constant interlayer insulation film is mentioned. In particular, organosilicate glass is preferable. These films are formed by the CVD method, the spin coating method, the dip coating method, or the spray method.

As a polishing device, for example, when polishing with a polishing cloth, a general polishing device having a holder capable of holding a substrate to be polished, a motor connected to a motor capable of changing the rotation speed, and a surface plate to which the polishing cloth is bonded can be used. have. As the polishing cloth, a general nonwoven fabric, foamed polyurethane, porous fluororesin, or the like can be used, but there is no particular limitation. Although there are no limitations on the polishing conditions, a low rotation of 200 rpm or less is preferable so that the rotational speed of the surface plate does not protrude. It is preferable that the pressurization pressure (polishing pressure) of the semiconductor substrate which has a to-be-polished surface to a polishing cloth is 1-100 Pa, and in order to satisfy | fill in-plane uniformity of a CMP speed and flatness of a pattern, it is more preferable that it is 5-50 Pa. desirable. While polishing, the polishing cloth for CMP is continuously supplied to the polishing cloth by a pump or the like. Although there is no restriction | limiting in this supply amount, It is preferable that the surface of an abrasive cloth is always covered with polishing liquid. It is preferable to wash the board | substrate after completion | finish of grinding | polishing well in flowing water, and to shake off the water droplets adhered on a board | substrate using spin-drying, etc., and to dry. In order to perform chemical mechanical polishing by always making the surface state of an abrasive cloth the same, it is preferable to add the conditioning process of an abrasive cloth before grinding | polishing. For example, the polishing cloth is conditioned with a liquid containing at least water using a dresser with diamond particles attached thereto. Then, it is preferable to perform the chemical mechanical polishing process which concerns on this invention, and also to add a board | substrate cleaning process.

The polishing method of the present invention can be applied, for example, to the formation of a wiring layer in a semiconductor device. EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the grinding | polishing method of this invention is described along with formation of the wiring layer in a semiconductor device.

First, an interlayer insulating film such as silicon dioxide is laminated on a silicon substrate. Subsequently, by a known means such as resist layer formation, etching, or the like, recesses (substrate exposed portions) of a predetermined pattern are formed on the surface of the interlayer insulation film to form interlayer insulation films having convex portions and recesses. On this interlayer insulating film, a barrier layer such as tantalum which covers the interlayer insulating film along the unevenness of the surface is formed by vapor deposition or CVD. Further, a metal conductive material layer such as copper covering the barrier layer to fill the recess is formed by vapor deposition, plating or CVD. The thickness of the interlayer insulating film, barrier layer and conductive material is preferably 0.01 to 2.0 µm, 1 to 100 nm and 0.01 to 2.5 µm, respectively.

Next, the conductive material layer on the surface of the semiconductor substrate is polished by CMP, for example, using a polishing liquid for the conductive material having a sufficiently large polishing rate ratio of the conductive material / barrier layer (first polishing). fair). As a result, a desired conductor pattern in which the barrier layer of the convex portion on the substrate is exposed on the surface and the conductive material film is left in the concave portion is obtained. This obtained pattern surface can be used as a to-be-polished surface for a 2nd grinding process, and can be grind | polished using a polishing liquid.

In the second polishing step, at least, the exposed conductive material of the barrier layer and the concave portion is polished by chemical mechanical polishing using the abrasive of the present invention which can polish the conductive material, the barrier layer and the interlayer insulating film. . The interlayer insulating film under the barrier layer of the convex portion is completely exposed, the conductive material layer serving as the wiring layer is left in the concave portion, and the polishing is performed when a desired pattern is obtained in which the cross section of the barrier layer is exposed at the boundary between the convex portion and the concave portion. To exit. In order to ensure more excellent flatness at the end of polishing, in addition, if the time until the desired pattern is obtained in the second polishing process is 100 seconds, in addition to the polishing of 100 seconds, 50 seconds is added. The polishing may be over-polishing 50%) to a depth including a part of the interlayer insulating film of the convex portion.

On the metal wiring thus formed, an interlayer insulating film and a metal wiring of the second layer are further formed, and an interlayer insulating film is formed again between the wirings and on the wirings, and then polished to smooth the entire surface of the semiconductor substrate. It is made with cotton. By repeating this step a predetermined number of times, a semiconductor device having a desired number of wiring layers can be manufactured.

The polishing liquid of the present invention can be used not only for polishing the metal film formed on the semiconductor substrate as described above but also for polishing a substrate such as a magnetic head.

Hereinafter, an Example demonstrates this invention. The present invention is not limited by these examples.

(Polishing solution manufacturing method)

The raw materials shown in Tables 1 to 6 were mixed in the respective formulations to prepare polishing liquids for CMP used in Examples 1 to 30 and Comparative Examples 1 to 8.

(Potential difference measurement)

The schematic diagram of an example of the measuring method of the potential difference in this invention is shown in FIG. As shown in FIG. 1, about 50 ml of the various CMP polishing liquids 2 prepared above were injected into a 100 ml glass beaker 1, and it was immersed in the constant temperature layer, and it maintained at 50 degreeC +/- 5 degreeC. A silicon substrate (hereinafter referred to as a copper substrate 4) formed with a copper film having a thickness of 1600 nm by the sputtering method, and a silicon substrate (hereinafter referred to as a barrier conductor substrate 3) formed with a tantalum nitride film having a thickness of 200 nm as a sputtering method. The size of 15 mm x 75 mm, and the positive electrode side of the electrometer 5 was connected to the copper substrate 4, and the negative electrode side was connected to the barrier conductor substrate 3. Thereafter, the minimum value of the potential difference from the time when the copper substrate and the barrier conductor substrate were immersed in the polishing liquid 2 for CMP 2 after a lapse of 30 seconds was measured so as not to contact each other. The potential difference measurement results of Examples 1 to 30 and Comparative Examples 1 to 8 are shown in Tables 7 and 8.

(Measurement of Solubility of Copper Complex)

In Examples 2 to 5, 7, 8, 21 to 30, and Comparative Examples 1 and 5 to 8, copper sulfate (II) was appropriately added to the CMP polishing liquid blended as shown in Tables 1 to 6, and then The presence or absence of a precipitate was confirmed. Below, the detail of the measurement concerning Comparative Example 5 and Example 2 is described.

Comparative Example 5: 2.6 g of copper sulfate (II) pentahydrate was added to 1000 g of the CMP polishing liquid formulated in the same manner as in Comparative Example 5 of Table 6, and after stirring well, the liquid temperature was maintained at 25 ° C. and left for 60 minutes. A green precipitate was seen. Here, the resulting complex of copper and 3-methyl-5-pyrazolone is estimated to be about 2.7 g, and the green precipitate is considered to be a complex of copper and 3-methyl-5-pyrazolone. Therefore, in this polishing liquid, it was found that the solubility of the copper complex produced when copper sulfate was added to the polishing liquid was less than 0.27% by weight at a liquid temperature of 25 ° C.

Example 2: After adding 1.85 g of copper sulfate (II) pentahydrate to 1000 g of the CMP polishing liquid blended as in Example 2 of Table 1, stirring well, the liquid temperature was maintained at 25 ° C. and left to stand for 60 minutes. No precipitate was seen in this solution. Here, the complex of copper and 1-hydroxybenzotriazole produced is estimated to be about 2.5 g. Subsequently, the liquid was concentrated in a reduced pressure dryer to 200 g, and the liquid temperature was maintained at 25 ° C. and left for 60 minutes, but no precipitate was observed. Therefore, in this polishing liquid, it was found that the solubility of the copper complex produced when copper sulfate was added to the polishing liquid was 1.25% by weight or more at a liquid temperature of 25 ° C.

The solubility of the copper complexes of Examples 2 to 5, 7, 8, 21 to 30 and Comparative Examples 1 and 5 to 8 were similarly investigated as described above and evaluated as follows. Indicated.

(Circle): The solubility of a copper complex is 1 weight% or more at 25 degreeC of liquid temperature,

X: The solubility of a copper complex is less than 1 weight% at 25 degreeC of liquid temperature.

―: Not rated

(Polishing of patterned substrate)

As a patterned substrate, SEMATECH854 CMP200 manufactured by SEMATECH (SEMIconductor MAnufacturing TECHnology) was polished only by a copper film which protruded by a known method, and the barrier layer of the convex part was exposed to the to-be-polished surface (1st polishing process). This substrate was used for the following polishing.

<Polishing condition>

Polishing pad: Foamed polyurethane resin (Rodel Corporation part number: IC1000)

Polishing pressure: 14㎪

Relative speed between substrate and polishing table: 70m / min

Supply amount of polishing liquid: 200 ml / min

Substrate Polishing Process

The pattern substrate was subjected to chemical mechanical polishing for 60 seconds under the polishing conditions with the polishing liquid for each CMP prepared above. This corresponds to the second polishing process, and all the interlayer insulating films of the convex portions were exposed to the surface to be polished by polishing for about 20 seconds, and the remaining 40 seconds were polished of the interlayer insulating films at the convex portions.

<Cleaning Step of Board>

The sponge brush (made of polyvinyl alcohol-based resin) was pressed onto the to-be-polished surface of the patterned substrate polished above, and the substrate and the sponge brush were rotated while supplying distilled water to the substrate, followed by washing for 90 seconds. Subsequently, the sponge brush was removed and distilled water was supplied to the surface to be polished of the substrate for 60 seconds. Finally, the substrate was dried at high speed by blowing distilled water.

<Evaluation Item>

The pattern wafer washed above was evaluated as shown in the following (1) and (2), and the results are shown in Tables 7 and 8.

(1) Copper wiring corrosion state: length measurement The isolated fine wiring part whose wiring width is 0.2-0.5 micrometer was observed using the scanning electron microscope, the corrosion state was investigated, and it evaluated as follows.

(Double-circle): Good without corrosion, (circle): A little corrosion is seen by a front end, but is generally good, (triangle | delta): A corrosion is seen by a front end, and a little corrosion is also seen by the boundary part of a wiring and a barrier layer. X: Not only the distal end portion of the wiring, but also a large number of corrosion portions are visible at the boundary between the wiring and the barrier layer.

(2) Flatness (discing amount): From the surface shape of the stripe-shaped pattern portion in which the width of the wiring metal (copper) portion of the pattern substrate and the interlayer insulating portion 100 width are alternately arranged, the interlayer insulating portion is touched with a tactile step. The film reduction amount (unit: kPa) of the wiring metal part was calculated | required.

As shown in Tables 7 and 8, in Comparative Examples 1 to 8, the potential difference exceeds 0.25 V, and not only the tip portion of the fine copper wiring of 0.2 to 0.5 µm, but also the corrosion portion is also present at the boundary between the copper wiring and the barrier layer. A large number was observed. In contrast, in Examples 1 to 30, the potential difference was 0.25 V or less, and the copper wiring corrosion state was also good. Moreover, the dishing amount was also small and the flatness was also favorable.

By the CMP polishing liquid of the present invention, the corrosion inhibiting effect of the conductive material fine wiring portion of the pattern substrate, in particular, the fine wiring portion of 0.5 µm or less, which often increases corrosion, is obtained. Moreover, the flatness of a pattern substrate is also excellent. The polishing method of the present invention which performs chemical mechanical polishing using this CMP polishing liquid is preferable for the production of semiconductor devices and other electronic devices having high productivity, excellent micronization, thinning, dimensional accuracy, electrical characteristics, and high reliability. Do.

This polishing liquid is excellent in flatness because the polishing rate ratio of the barrier layer, the conductive material wiring, and the interlayer insulating film can be adjusted. Moreover, this invention is providing the grinding | polishing method in manufacture of a semiconductor device etc. which are excellent in refinement | miniaturization, thin film formation, dimensional precision, high reliability, and low cost.

Claims (25)

When the positive electrode side of the electrometer is connected to the conductive material and the negative electrode side is connected to the conductor, the absolute value of the potential difference between the conductive material and the conductor at 50 ± 5 ° C. in the polishing liquid is 0.25 V or less, at least the conductor layer and the conductor layer. A polishing liquid for CMP for polishing a conductive material layer in contact with it. The polishing liquid for CMP according to claim 1, which contains an additive for lowering the absolute value of the potential difference between the conductor and the conductive material. The heterocyclic ring according to claim 2, which contains any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group and further contains at least one of a nitrogen and a sulfur atom. Polishing liquid for CMP containing 1 or more types chosen from a compound. The CMP polishing liquid according to claim 3, wherein the heterocyclic compound has a solubility of the copper complex produced when copper (II) is added to the polishing liquid to the polishing liquid at a liquid temperature of 25 ° C. The polishing liquid for CMP according to claim 2, which contains at least one selected from an amine compound, an amide compound and a sulfoxide compound as an additive for lowering the absolute value of the potential difference. The heterocyclic compound according to any one of claims 3 to 5, which contains any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group, and further contains at least one of nitrogen and sulfur atoms. Polishing liquid for CMP containing 1 or more types chosen from among, and 1 or more types chosen from an amine compound, an amide compound, and a sulfoxide compound. The conductor according to any one of claims 1 to 6, wherein the conductor is tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys. And at least one selected from other tungsten compounds, ruthenium and other ruthenium compounds, wherein the conductive material is copper, copper alloy, oxide of copper, oxide of copper alloy, tungsten, tungsten alloy, silver, silver alloy or Polishing solution for gold CMP. The polishing liquid for CMP according to any one of claims 1 to 7, wherein the conductive material is copper. Conductive material (a) containing copper as a main component, and Selected from tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys, other tungsten compounds, ruthenium, and other ruthenium compounds At least one conductor (b) Is a polishing liquid for polishing a to-be-polished surface having a surface thereof, and a conductive material at 50 ± 5 ° C. in a polishing liquid when the positive electrode side of the electrometer is connected to the conductive material (a) and the negative electrode side is connected to the conductive material (b) ( The polishing liquid for CMP, characterized in that the absolute value of the potential difference between a) and the conductor (b) is 0.25 V or less. Polishing a substrate having an interlayer insulating film having a concave portion and a convex surface, a barrier conductor layer covering the interlayer insulating film along the surface, and a conductive material layer mainly composed of copper filling the concave portion to coat the barrier conductor layer. A polishing liquid, containing any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, and a sulfinyl group, and at least one member selected from a heterocyclic compound containing at least one of nitrogen and sulfur atoms. CMP polishing liquid, characterized in that. Conductive material (a) containing copper as a main component, and Selected from tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys, other tungsten compounds, ruthenium, and other ruthenium compounds At least one conductor (b) Is a polishing liquid for polishing a surface to be polished having a surface thereof, a heterocyclic compound containing any one of a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group and a sulfinyl group, and containing at least one of nitrogen and sulfur atoms Polishing liquid for CMP containing 1 or more types chosen from. Polishing a substrate having an interlayer insulating film having a concave portion and a convex surface, a barrier conductor layer covering the interlayer insulating film along the surface, and a conductive material layer mainly composed of copper filling the concave portion to coat the barrier conductor layer. A polishing liquid, wherein the polishing liquid for CMP contains at least one selected from an amine compound, an amide compound, and a sulfoxide compound. Conductive material (a) containing copper as a main component, and Selected from tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, titanium nitride, titanium alloys, other titanium compounds, tungsten, tungsten nitride, tungsten alloys, other tungsten compounds, ruthenium, and other ruthenium compounds At least one conductor (b) A polishing liquid for polishing a surface to be polished having a surface thereof, wherein the polishing liquid for CMP contains at least one selected from an amine compound, an amide compound, and a sulfoxide compound. The polishing liquid for CMP according to any one of claims 1 to 13, which contains abrasive particles. The polishing liquid for CMP according to claim 14, wherein the abrasive particles are at least one selected from silica, alumina, ceria, titania, zirconia, and germania. The polishing liquid for CMP according to any one of claims 1 to 15, which contains a metal oxide solubilizer and water. The polishing liquid for CMP according to claim 16, wherein the metal oxide solubilizer is at least one selected from organic acids, organic acid esters, ammonium salts of organic acids, and inorganic acids. The polishing liquid for CMP according to any one of claims 1 to 17, which contains a metal corrosion inhibitor. The metal corrosion inhibitor according to claim 18, wherein the metal corrosion inhibitor has a triazole skeleton, a benzotriazole skeleton, a pyrazole skeleton, a pyramidine skeleton, an imidazole skeleton, a guanidine skeleton Polishing liquid for CMP which is 1 or more types chosen from thing which has a thiazole skeleton. The polishing liquid for CMP according to any one of claims 1 to 19, comprising an oxidizing agent of a metal. The polishing liquid for CMP according to claim 20, wherein the metal oxidant is at least one selected from hydrogen peroxide, nitric acid, potassium periodate, hypochlorous acid, and ozone water. Polishing a conductive material layer on a substrate having an interlayer insulating film having a concave portion and a convex portion, a barrier conductor layer covering the interlayer insulating film along the surface, and a conductive material layer filling the concave portion to cover the barrier conductor layer; 22. The chemical polishing apparatus of claim 1 wherein the barrier conductor layer of the convex portion is exposed, and at least the barrier conductor layer and the conductive material layer of the concave portion are supplied with the polishing liquid for CMP according to any one of claims 1 to 21. And a second polishing step of polishing to expose the interlayer insulating film of the convex portion. The polishing method according to claim 22, wherein the interlayer insulating film is a silicon based film or an organic polymer film. The polishing method according to claim 22 or 23, wherein the conductive material is mainly composed of copper. 25. The barrier conductor layer according to any one of claims 22 to 24, wherein the barrier conductor layer prevents diffusion of the conductive material into the interlayer insulating film, and includes tantalum, tantalum nitride, tantalum alloys, other tantalum compounds, titanium, and titanium nitride. And a titanium alloy, other titanium compounds, tungsten, tungsten nitride, tungsten alloy, other tungsten compounds, ruthenium, and at least one selected from other ruthenium compounds.

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